Process for the biological treatment of wastewater with periods of biomass starvation

Abstract

A biological treatment of wastewater from intermittent and/or sporadic sources is described. The process includes the step of: maintaining treated wastewater effluent and biomass in a quiescent state without stirring, aeration or agitation during biomass starvation wherein said biomass retains the capacity for biological wastewater treatment following the period of prolonged biomass starvation.

I claim: 
     
       1. A process for conditioning a biomass, said biomass to be used to process a feedstock, comprising the steps of: 1) adding a wastewater feedstock to a biomass to form a mixed liquor;   2) permitting said mixed liquor to generate an anoxic atmosphere;   3) mixing said mixed liquor for a first pre-determined time;   4) aerating said mixed liquor to create an aerobic atmosphere;   5) mixing said mixed liquor for a second pre-determined time; and   6) holding said mixed liquor without further aeration and without further mixing to provide a regeneratable biomass for processing a wastewater feedstock in a wastewater treatment process.   
     
     
       2. A process as claimed in claim 1, wherein said process further includes a step of allowing said mixed liquor to generate an anoxic atmosphere for a third predetermined time. 
     
     
       3. A process as claimed in claim 2, wherein said third predetermined time is at least 15 minutes. 
     
     
       4. A process as claimed in claim 1, wherein said wastewater feedstock is a source of carbon, nitrogen and phosphorous. 
     
     
       5. A process as claimed in claim 1, wherein said anoxic atmosphere contains less than 0.7 ppm oxygen. 
     
     
       6. A process as claimed in claim 1, wherein said first pre-determined time is at least 210 minutes. 
     
     
       7. A process as claimed in claim 1, wherein said aerobic atmosphere contains at least 1 ppm oxygen. 
     
     
       8. A process as claimed in claim 1, wherein said second pre-determined time is at least 180 minutes. 
     
     
       9. A process as claimed in claim 1, wherein said step of holding occurs at a temperature within the range of approximately 20.5° C. to 28° C. 
     
     
       10. A process as claimed in claim 1, wherein said step of holding occurs at a temperature within the range of approximately 20.5° C. to 24° C. 
     
     
       11. A process as claimed in claim 1, wherein said step of holding is for a period of at least 60 days. 
     
     
       12. A process as claimed in claim 1, wherein said process further includes a step of regenerating said biomass to restore its wastewater treatment capabilities. 
     
     
       13. A process as claimed in claim 12, wherein said step of regenerating said biomass includes aerating and mixing said biomass. 
     
     
       14. A process as claimed in claim 13, wherein said step of regenerating includes a further step of feeding said biomass. 
     
     
       15. A process as claimed in claim 12, wherein said wastewater treatment capabilities include the ability to remove nitrogen, phosphorous and chemical oxygen demand from said wastewater feedstock.